This page gives only a short summary and points readers to the original Ligonier article by R.C. Sproul.
The article answers the objection that limited atonement removes the motivation for evangelism. Sproul argues that historic Calvinism still calls Christians to preach Christ freely to all people, while grounding evangelistic confidence not in human persuasion but in the effective saving work of Christ.
The heart of the argument is that Christ's death did not merely make salvation possible. He actually accomplished redemption for his people. Therefore, the evangelist can proclaim the Gospel boldly, trusting that the Good Shepherd will call his sheep and that those who hear his voice will come to him.
For the full article and the original argument, please read the Ligonier article linked below.